As a communication technology develops recently, an interchangeable-lens camera or a camera with an interchangeable lens is brought to the market. Since an interchangeable-lens camera supports a wireless access function, it enables shooting of a photo and a moving picture even when a main body and a lens unit are physically separated. The main body and the lens unit have a wireless module for wireless connection between them. This wireless module needs to be determined with consideration of a photo to be exchanged between the main body and the lens unit, or a bandwidth of a moving picture.